body {
    margin: 0;
    padding: 20px;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: #f5f7fa;
    color: #333;
    height: 100vh;
    box-sizing: border-box;
  }
  
  #container {
    max-width: 1400px;
    margin: 0 auto;
  }
  
  header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
  }
  
  .controls {
    display: flex;
    gap: 15px;
  }
  
  #month-selector {
    padding: 8px 12px;
    border-radius: 4px;
    border: 1px solid #ddd;
  }
  
  #fullscreen-btn {
    background: #4a90e2;
    color: white;
    border: none;
    padding: 8px 16px;
    border-radius: 4px;
    cursor: pointer;
    transition: background 0.3s;
  }
  
  #fullscreen-btn:hover {
    background: #357ae8;
  }
  
  #stats {
    display: flex;
    justify-content: space-around;
    margin-top: 30px;
  }
  
  .stat-card {
    background: white;
    border-radius: 8px;
    padding: 20px;
    text-align: center;
    box-shadow: 0 2px 12px rgba(0,0,0,0.1);
    width: 30%;
  }
  
  .stat-card h3 {
    margin-top: 0;
    color: #666;
  }